Varipitch spiral blade impeller or turbine



May 21, 1940. K. s. VALENTINE VARIPITCH SPIRAL BLADE IMPELLER 0R TURBINE Filed March 16, 1938 gin/02mm Llam Patented May 21, 1940 UNITED STATES VARIPITCH SPIRAL BLADE DIPELLER OR TURBINE Kenneth S. Valentine, New York, N. Y., assignor to The Patterson Foundry & Machine 00., East Liverpool, Ohio, a corporation of Ohio Application March 16, 1938, Serial No. 196,296 4 Claims. (01. 259-103 This invention relates to an improvement in varipitch spiral blade impellers or turbines.

This particular construction is used for mixing operations, and the objects are to provide for faster blending and dissolving the material ,operated upon, and it might be mentioned in this connection that the speed of dissolving very often depends on maintaining a high velocity of travel of every particle within a container in which this improved turbine operates. My improved turbine or impeller by virtue of its directional throw, permits better action at the'upper and lower corners of the container, and thus helps to speed up the dissolving operation. This also applies to blending and mixing as well.

Another object is to provide means for causing the discharge currents to reach out further into the container. Y

Still another object is to accomplish a better intermixing of upper and. lower layers, due to the appreciable vertical component at the tips of the blade; and in the mixing of viscous materials these advantages are incalculable since they furnish a definite directional impulse.

With the foregoing objects in view, this improved turbine has curved blades, and in vertical section these blades are pitched in varied vertical planes, so as to impart simultaneously upward and downward direction to the material which is discharged from the blades of the impellers as the turbine rotates. In other words, the material is all discharged in a substantially horizontal direction, and to accomplish this, approximately half of the blades point or incline upwardly, and approximately half point or incline downwardly, thereby giving approximately one-half of thematerial a flip in one direction and one-half in another direction for every r0- tation of the impeller, the blades being set at variable vertical angles so that this change of upward to downward movement will be gradual and not sudden, it having been determined that the direction of flow of viscous materials can only be changed very gradually since any attempt to change it suddenly will defeat the purpose of the invention.

In the accompanying drawing:

Fig. 1 is a view looking down on the turbine or impeller, and

Fig. 2 is a side elevation.

The turbine or impeller as a whole is represented by the letter A, and it is adapted to be secured to a rotary shaft I, by means of a key (not shown) in the key-way 2 formed in the hub 3; and set-screws (not shown) in the threaded holes 4 in the hub. The blades extend more or less tangentially from the hub in a general curve as shown in Fig. 1, and these are gradually turned or twisted throughout their length to different angles, preferably with half of them turned up different degrees at their tips, and the remaining half down at theirtips. For example, blades 5 and I are turned upat an angle of say 15 and the intermediate blade 6 up at an angle of and the blades 8 and III are turned downat an angle of 15, and the blade 9, down at an angle of 30.

The turbine or impeller is adapted to be used in any approved machine designed to receive it. and for the purpose of dissolving, blending and mixing viscose and other materials.

With the construction of the foregoing type of machine, the various objects and advantages hereinbefore outlined are attained, and the problems of the past have been satisfactorily solved, with the result that faster blending has been accomplished by overcoming the hitherto sluggish motion at the wall or at the top or bottom corners of the vessel by preventing undissolved particles from lagging at these points or areas, which would otherwise delay the completion of the dissolving process since dissolving cannot be considered complete until every particle under treatment shall have been dissolved.

I claim: a

1. A varipitch spiral blade impeller or turbine including a plurality of curved blades, a certain number of which are twisted upwardly and a certain number downwardly toward their tips, the center blade of the sets of blades twisting either upwardly or downwardly at a greater degree than those on either side thereof.

2. A varipitch spiral blade impeller or turbine including a plurality of curved blades, an equal number of which are twisted up 15 at the tips, and down 15 at the tips, and an equal number of intermediate blades twisted up 30 at the tips and down 30 at the tips, in order to be inclined from the axis.

3. A varipitch spiral blade impeller or turbine including a hub and blades which are approximately parallel with the axis of the hub at the end adjacent to the hub, and gradually twist and curve as they approach their outer ends, the twist differing in difierent blades.

4. A varipitch spiral blade impeller or turbine including a hub and a plurality of curved blades, a certain number of which blades are twisted upwardly and a certain number downwardly toward the tips, and an equal number of intermediate blades similarly twisted approximately at twice the angle of the aforementioned blades toward the tips in order to be inclined from the axis.

KENNETH S. VALENTINE. 

